When we use cationic dyes for dyeing, many factors will affect the dyeing effect.

Therefore, in order to ensure the dyeing effect, we need to pay attention to these aspects.

Cangzhou Xincheng Weiye Chemical Co., ltd is produing various cationic dyes for 26 years, our main products include cationic red 46, cationic yellow X-GL, cationic blue 3, cationic blue 159, cationic violet 16.

Let’s take a look at the three factors that affect the dyeing effect with cationic dyes?

1. Temperature

Temperature is an important factor in controlling level dyeing. When acrylic fiber is dyed with cationic dyes, there is little dye uptake below 75 ℃. When the dyeing temperature reaches the glass transition temperature (75-85 ℃), the dye uptake rate increases rapidly. Therefore, when the dyeing temperature reaches the glass transition temperature of the fiber, it should be heated slowly, generally 1 ℃ every 2 ~ 4 minutes. It can also be dyed at 85 ~ 90 ℃ for a period of time, and then continue to heat up to boiling.

2. PH value of dyeing bath

Adding acid to the dyeing bath can inhibit the dissociation of acid groups in acrylic fiber, reduce the number of anion groups on the fiber, reduce the Coulomb attraction between dye and fiber and reduce the dyeing rate. The effect of pH value on the dyeing rate is more significant for acrylic fiber containing carboxylic acid group, and the dyeing rate of acrylic fiber containing sulfonic acid group is less affected by the pH value of dyeing bath. The pH value of the dyeing bath shall be reasonably controlled during dyeing. Cationic dyes are generally not alkali resistant, and the optimal pH value for dyeing is generally 4-4.5. When dyeing dark colors, the pH value of the dyeing bath can be higher, and when dyeing light colors, it should be carried out at a lower pH value. The pH value of the dyeing bath is generally adjusted with acetic acid. Acetic acid can not only reduce the pH value of the dyeing bath, but also improve the solubility of dyes. Adding sodium acetate to the dyeing bath at the same time can stabilize the pH value of the dyeing bath within the required range.

3. Electrolyte

Adding electrolytes, such as sodium sulfate and salt, to the dyeing bath can reduce the dyeing rate of cationic dyes and slow down the dyeing. Electrolyte has no obvious retarding effect on dyes with K value of 1 ~ 1.5, but has retarding effect on dyes with K value of 3 ~ 5. The retarding effect of electrolyte decreased with the increase of dyeing temperature. When dyeing light color, the amount of electrolyte can be higher, about 5% ~ 10% (o.w.f.), but not when dyeing dark color.

The factors affecting the dyeing effect of cationic dyes are temperature, pH value of dyeing bath and electrolyte. Therefore, we must pay attention to the above knowledge when dyeing.

Contact person: Miss Jessie Geng

Email:jessie@xcwychem.com

Mobilephone/Whatsapp: +86-13503270825